Plate valves



July 9, 1957 T. K. KEHLER 2,798,505

PLATE VALVES Filed May 4, 1954 2 Sheets-Sheet 1 C P 2 x .I 1/ L II 9 w Q fla y 1957 T. K. KEHLER 2,798,505

PLATE VALVES Filed May 4, 1954 2 Sheets-Sheet 2 CZYIIITIIID Fig. 5 :3

'I/ l II United States Patent PLATE VALVES Theodor Karl Kehler, Vienna, Austria, assignor to Honbiger & Co., Vienna, Austria Application May 4, 1954, Serial No. 427,506

Claims priority, application Austria August 11, 1953 9 Claims. (Cl. 137 51611) Non-return plate valves are used in two-stroke internal combustion engines with scavenging pump arrangements or crank-case scavenging arrangements. Such a valve, for better utilization of the available surface area, is generally of rectangular plan form. The rectangular valve seating is provided with a number of rectilinear slots or openings which are individually closed by plates attached to the valve seating, the plates by their elastic deformation under fluid pressure intermittently uncovering the slots in the valve seating. It is possible to arrange above the plates and at a certain distance therefrom, an intercepting element or guard which damps the natural vibrations of the plates and restricts their stroke or the amount of their lift. A disadvantage of such an arrangement is that the plates, which are attached to the valve seating in line with the slots in the latter, do not free the slots over their whole length to the same extent or with the same amount of lift. Arrangements by which the plates are bent upwards in parts not covering the slots and are there connected with the guard are unsuitable in plate valves of small sizes.

Another known kind of plate valve has as a common element closing all the longitudinal slots of the valve seating, a single, slotted metal plate slidably guided on two cylindrical bolts or pins. The slots of the plate are so arranged that when the valve is completely assembled, they are located between the slots of the valve seating and thus when the valve is opened afford a sufiiciently large free area for the passage of the working medium. The plate bears against the guard through the intermediary of a spring or elastic element which is of nearly the same plan form as the plate and is arched in the direction of the slots, the chord depth of curvature being greater than the intended distance between the plate and the guard. The slidable guiding on two bolts or pins has a disturbing etfectwhen, as is most frequently the case, the valve is not situated in a horizontal plane and is required to work at a high frequency. On the other hand, such a plate valve has a parallel lift of the plate which is advantageous for the proper functioning of the valve.

It is the object of the present invention to provide an improved and more efiicient form of plate valve.

A plate valve in accordance with the invention comprises a valve seat having a number of parallel fluidadmission slots, a valve plate which co-acts with said seat and is provided with slots most of which do not extend as far as to the edge of the plate so that the strips covering the slots of the seat are interconnected by common transverse connecting portions whereas those slots of the valve plate which are next to the marginal strips extend as far as to the edge of the plate owing to a parting of one of said transverse connecting portions, so that the marginal strips take the form of flexible links, each strip and each marginal strip formed as a link closing a fluid-admission slot of the valve seat and each of the links having one free end, and means anchoring the tree ends of the links to the valve seat.

2,798,505 Patented July 9, 1957 Thus, in the plate valve of this invention, the guide links of the single valve plate act in the same manner as the flexiblyattached plates previously mentioned and only partially uncover the pertaining fluid-admission slots of the valve seating when the valve plate lifts, but the remainder or body part of the valve plate acts in the manner of a slidably guided valve plate and uncovers the whole area of the other fluid-admission slots of the valve seating.

A further feature of the invention consists in attaching the free ends of the guide links of the valve plate to the valve seating by shouldered bolts which also serve as spacers and attachment means for a guard plate which is parallel to the seating plate throughout its extent.

Still a further feature of the invention resides in providing resilient means for closing the valve plate in the form of a spring plate similarly slotted to the valve plate and presenting guide strips each free at one end while the remainder of the spring plate is arched in such manner that the height of the crown of the arch is less than the free stroke or lift of the valve plate. Such a spring plate can be assembled with the arch crown either adjacent the valve seating or adjacent the guard plate of the valve, the freeends of the guide strips being anchored either to the valve seating or to the guard plate. By suitable arrangement of the attachment and shaping of its guide strips, it is possible to ensure that the spring plate abuts when the valve is closed either against the valve plate or the guard plate. In the former case, both the valve plate and the spring plate require to be accelerated at the instant of opening of the valve; in the latter case, only the valve plate requires to be accelerated, which is advantageous for valves required to work at high frequencies.

An advantage of this last mentioned arrangement is that the lifting of the small mass of the valve plate at the beginning of the lift or stroke is opposed only by the spring force of the valve plate guide links and by the spring plate guide strips, while the spring force of the actual, arched portions of the spring plate becomes efiective only towards the end of the valve lift or stroke, which facilitates rapid opening of the valve and effective damping of the opening shock.

The invention will be clearly understood from the foregoing and the following description of certain embodiments which are given by way of example and are illustrated on the accompanying drawings.

Fig. 1 of the drawings is an elevation of a valve with a link-guided valve plate in which the guide links extend from the same end of the plate.

Fig. 2 is a plan corresponding to Fig. 1, the guard (8) being omitted.

Fig. 3 is a perspective view of the spring plate which rests when the valve is closed on the valve plate so that there is a clearance between the spring plate and the guard.

Fig. 4 is an elevation of a plate valve in which the guide links of the valve plate extend from opposite ends of the plate.

Fig. 5 is a plan corresponding to Fig. 4, the guard (8) being omitted.

Fig. 6 is a perspective view of the spring plate of the last mentioned valve, which spring plate rests when the valve is closed against the guard so that there is a clearance between the valve plate and the spring plate.

Fig. 7 is a plan of a plate valve of circular form, the guard being again omitted.

Throughout the several figures the same references are used to denote the same or similar parts.

In each of the illustrated embodiments 1 denotes the valve seating provided with admission slots 2; 3 the valve plate provided with admission slots 4 and with fluid admission slots 4 1, which are extended by parting slots as far as to an outer edge of the plate, so that the marginal strips form guide linksS; 6 the arched spring plate having two guidetstrips-7; and-tithe guard plate. Shouldered bolts 9: each having screwthreads 1-0. at both of; its ends serve the purpose of holding the guide links 5 of thevalveplatefi against the val-ve seating'1'as-,.well as maintaining the guard Sin therequired spacedjposition. Referring now particularly to the valve illustrated by Figs.'1:-to-3, it will be seen that the freeends of the guide links Set the valve plate 3. and of guide strips 7 of the spring plate 6 are on the same side of the rectangle. This accordingly-fixes the-.positionof the-bolts 9. .Such

unilateral arrangement of the bolts 9, which also hold the;guard18.in;place, would cause-them to beaunfavourably stressed .owing to the 'openingashocksof the valve. It is, consequently, advantageous to provide the valve seatingll with a third; bolt-11 which only has the purpose of holding the :guard in position with reference to the valve seating. The valve plate 3 and the spring plate 6 are then provided with appropriate clearance notches 12. :Further, the arrangement of the spring plate 6, shownrin .Fig. 1, is such that the points of attachment of its guide strips 7 are directly overthe points of attachmerit of the valve plate guide links 5, and a clearance is provided-between the arched springplate 6 andthe guard 8. The convex side .of the spring plate 6 is directed towards the guard 8, .that is to say the crown of the arch isadjacent the guard.

In the valve shown in Figs. 4 .and 5, the free ends of the two valve plate guide links 5 and of the two spring plate guide strips '7 are diagonally .opposite, so that the attachment bolts 9 are situated on a diagonal of the valve seating 1. Since the resultant .of the forces acting onthe guard 8 in this case coincides in direction with the connecting line between the guide link and guide attachments, a third spacing bolt for the guard plate is unnecessary. The arrangement ,of the arched spring plate 6 in this example is such that its convex part is directed towards the valve plate 3,'that is to. say the crown of the arch is adjacent the valve seating. Opposite ends of the spring plate 6 abut against the guard 8 and there is a clearance between the spring plate 6 and the valve plate 3. The guide strips 7 of the spring plate 6 in contact with the guide links 5 of the valve plate 3 are anchored by the shouldered bolts 9.

In the plate valve shown in Fig. 7 for a circular valve seating 1,.the valve plate 3 and the spring plate 6 are shaped substantially similarly to those of Figs. 1 to 3. The screw-threaded shouldered bolts 9 are in this case used only for attaching the valve guard (not shown in Fig. 7). The attachment of the valve plate guide links 5 and the spring plate guide strips 7 is effected by roundheaded screws 13, the heads of which are covered by the guard.

A; particular advantage of a plate .valve in accordance with the invention is the .efiicient utilization of the available surface area of the valve seating, which is attained by virtue of the fact that the area under the guide links and guide strips is also utilized for admission. A further advantage is that this arrangement allows by the use of a suitable spring plate an eifective damping of the opening shock.

I claim:

1. A plate valve comprising a valve seat having a number of parallel fluid-admission slots, a valve plate which co-acts with the seat and is provided with slots most of whichdo not extendas far as tothe edge of the plate so that the strips covering the slots of the valve seat are interconnected by common transverse connecting portions whereas those slots of the valve plate-which are next to the marginal strips extend asfar as to the edge of the plate owing to a parting of one of said transverse connecting portions, so that :the marginal strips take the formof flexiblelinks, eachstrip and each'marginal strip valve plate slotted to present parallel bands and flexible guide..links,.each: of thezbands .and each of the guide links effective to close at least one-0fthe fluid-admission slots of the valve seatingand each of the guide links having one free end, means anchoring the free ends of the guide links toitheivalvc-seating' and forming the sole attachment of said valve plate to said valve seating, and an arched spring plate slotted similarly to the valve plate and presenting guide strips each with a free end anchored by the said anchoring means, the theight'of .the crown of the arch of the spring plate being less than the lift of the valve plate.

3. A plate valve comprising a valve seating having a number .of parallel fluid-admission slots, aco-acting valve plateslotted to present parallel bands and flexible guide links, each of the bands and each of the guide links effective to close at least one of the fluid-admission slots of the valve seating and each of the guide links having one free end, means anchoringthe free ends of-the guide links to the valve seating, a guard plate spaced from and parallel with the valve seating. and forming the sole attachment of said valve plate to said valve seating, and an arched spring plate slotted similarly to the valve plate and presenting guide strips each with a free end anchored by the said anchoring means, the crown of the arch being less in height than the lift of the valve plate and situated adjacent the guard plate.

4. A plate valve comprising a valve seating having a number of parallel fluid-admission slots, a co-actingvalve plate slotted to present parallel bands and flexible guide links, eachof the bands. and each of the guide links effective to close at least one of the fluid-admission slots of the valve seating andeach of the guide links having one free end, means anchoring the free ends of the guide links to the valve seating and forming the sole attachment of said valve plate to said valve seating, a guard plate spaced from the valve seating, and an arched spring plate,

slotted similarly to the valve plate and presenting guide strips each with a free end anchored .by the said anchoring means, the crown of the arch being less in height than the lift ofthe valve plate and situated adjacent the valve seating.

5. A plate valve comprising a valve seating having a number of parallel fluid-admission slots, a co-acting valve plate slotted to present parallel bands and flexible guide links,.each of the bands and each of the guide links effective to close at least one of the fluid-admission slots of the valve seating and each of the guide links having one free end, a guard plate spaced from the valve seating, an arched spring plate slotted similarly to the valve plate and presenting guide strips each with. one free end, and shouldered'bolts securing the guide strips of the spring plate and the guide links of the valveplate'in superposition to the valve seating at their free ends and forming the sole attachments of said spring plate and said valve plate to the valve seating, the same bolts also securing the guard plate.

6. A plate valve comprising a valve seating having a number of parallel fluid-admission slots, a co-acting valve plate slotted to present parallel bands and flexible guide links, each of the bands and each of the guide links effective to close at least one of the fluid-admission slots of the valve seating and each of the guide links having one free end, a. guard plate spaced from the valve seating, an arched spring plate slotted similarly to the valve plate and presenting guide strips each with one free end, and shouldered'bolts securing the guide strips of the spring plate and the guide links of the valve plate in superposition to the valve seating at their free ends and forming the sole attachments of said spring plate and said valve plate to the valve seating, the same bolts also securing the guard plate, the crown of the arch being less in height than the lift of the valve plate and adjacent the guard plate. 7

7. A plate valve comprising a valve seating having a number of parallel fluid-admission slots, a co-acting valve plate slotted to present parallel bands and flexible guide links, each of the bands and each of the guide links eifective to close at least one of the fluid-admission slots of the valve seating and each of the guide links having one free end, a guard plate spaced from the valve seating, an arched spring plate slotted similarly to the valve plate and presenting guide strips each with one free end, and shouldered bolts securing the guide strips of the spring plate and the guide links of the valve plate in superposition to the valve seating at their free ends and forming the sole attachments of said spring plate and said valve plate to the valve seating, the same bolts also securing the guard plate, the crown of the arch being less in height than the lift of the valve plate and adjacent the valve seating.

8. A plate valve comprising a rectangular valve seating having a number of parallel fluid-admission slots, a coacting rectangular valve plate slotted to present parallel bands and flexible guide links, each of the bands and each of the guide links efiective to close at least one of the fluid-admission slots of the valve seating and each of the guide links having one free end, and means anchoring the free ends of the guide links to the valve seating and forming the sole attachment of said valve plate to said valve seating.

9. A plate valve comprising a circular valve seating having a number of parallel fluid-admission slots, a coacting valve plate slotted to present parallel bands and flexible guide links, each of the bands and each of the guide links effective to close at least one of the fluid-admission slots of the valve seating and each of the guide links having one free end, and means anchoring the free ends of the guide links to the valve seating and forming the sole attachment of said valve plate to said valve seatmg.

References Cited in the file of this patent UNITED STATES PATENTS 1,287,530 Voss Dec. 10, 1918 1,299,762 Nelson Apr. 8, 1919 1,682,906' Holdsworth Sept. 4, 1928 2,344,818 Hutton Mar. 21, 1944 FOREIGN PATENTS 443,165 France of 1912 

